Official Luthiers Forum!

I would think that fretting a board alone, off the neck by itself, would cause it to roll up like one of them rolly pollies. If the idea is that yes that does happen but then when you glue it flat down it puts a favorable back bow force on a neck that is about to be tensioned to forward bow with strings then I get that.

Ken, if your upper bout is exactly co-planar with the neck angle and no drop off is sanded into the already fretted fingerboard do you ever have problems with a rising extension after things settle in under tension?

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I do like Ken. But, with my geometry (1.5° angle/30' top radius), I usually get a nice 20 thou rise at the end of the fretboard which when I glue it down becomes my fall away.

Are you fret later guys sanding the Fall Away into the end of the fretboard?

I have been getting good results without a very sophisticated system, although I do use a very stiff gluing caul that is dead flat.

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Pat

Yes - the board and fret plane is completely shaped and perfected with the board on the neck and the neck on the guitar. This is our opportunity to shape the fret plane as we wish including the following:

1) Compound or fixed radius

2) Relief where we want it and not where we don't want it i.e. more on the bass side less on the treble side

3) Create and/or perfect fall-away and to what degree

4) I'll add slight adjustments of neck angle, that's right even the neck angle can be slightly changed as desired leveling the board on the guitar. In the repair world this can belay the need for a neck reset for a few more years and save the current steward of the ax big bucks

All these things can be had/achieved completely independent of the frets so that when we do fret very minimal fret material has to be removed to shape the fret plane as desired. This also means that the time before a refret is extended and that equates to "value" for the steward of the guitar. Not only is everything completely serviceable measures have been taken to extend the life of the fret plane by minimizing fret material removal.

There is no doubt that fretting on the guitar, shaping the board on the guitar provides options and even value that cannot be achieved by most.... mere mortals who don't have a strict process control system and the experience to have refined the method and system over time and experience.

There is a reason why the PLEK has proliferated and more and more precision is desirable in the fret planes of our instruments. More demanding players may require this precision, low action folks certainly do.

I'll back Hesh & Dave on this as long as they want I just got back from their class with a big loud D-18 with medium strings and let's just say it plays like butter, easy to tune and the intonation is great

I am actually putting some fall away in the angle of the upper bout. If you were to lay a fretboard on my upper bout a straightedge would hit just at the top of the bridge. My Bourgeois attachment system moves a little more than a glued extension. If I think I need more I sand it into the end of the fretboard.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

While we do no use a cantilevered neck block like Martin, our block design is substantial there is also a Popsicle brace and a hefty shoulder brace. But no I have not seen that condition on our guitars and for that matter I've never seen that happen on a modern Martin. but it sounds like it can.

Let me qualify -- as usual I have no intention of making an argument for what is the "very best" for this or any other guitar making procedure or tool. KMG caters to new comers in this marvelous hobby -- we take our customers down a path where they can gain experience in dealing with acoustic guitar geometry and in the end have a very respectable instrument they can show off with pride. The key being they do not have to invest a fortune to do so -- is that a bad thing? Factory methods, Martin, Taylor Larivee, Yamaha etc. are the basis for many of the KMG methods -- because they work and are repeatable. As Hesh mentioned these factory guitars are not tweaked to perfection and ready for the demands of best players in the world -- and neither are our sometimes first time builders kits or scratch projects -- we walk before we run. Plus there are always after market refinements and adjustment -- all part of the luthier's craft.

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Ken Cierp

http://www.kennethmichaelguitars.com/

This was a hot topic in the shop for a bit a few weeks ago - primarily because I was questioning why we could not just set up the press (we have several, including the Jaws series) and get every waiting fretboard ready to go. As with Dr. Kennedy's and Mr. Breakstone's new construction, we fret after finishing and assembly, with final fret plane determination done primarily as a consequence of final leveling of the fretboard. Our reasons for doing so are rooted in the intention to control not only the geometry of the fretboard extension, but - and this is important - the final string height above the top at the saddle.

While Martin may elect to fret their boards prior to neck assembly, and use what is described as tight process control to minimize variation in the outcomes, they still appear to have to employ several different finished thicknesses on their bridges to address what appears to be an .080" - .100" difference between string height at the saddle in their finished guitars. The other luthiers here in the shop have seen at least four distinct bridge thicknesses used, from 0.290" to over .400" for instruments built in the period from the mid-1990's until recently, and expressed the general opinion that Martin's fretting prior to neck assembly may be less focused on controlling final geometry than in reducing production costs.

I cannot speak for either Dr. Kennedy or Mr. Breakstone, but in this shop, that sort of variation in the final instrument geometry would be referred to as "...less than optimal...def AFU...need to trim that (stuff) up." This is the reason I was given as to why we fret new acoustics after finishing and assembly, and build our fretting preparation and installation process around the practice - it allows us to make final, fine adjustments in the fretboard plane to minimize variation in bridge thickness and saddle height at the desired action.

I should mention that we think highly of Mr. Proulx's instruments here, have great admiration for his ability to control instrument geometry to achieve his desired outcomes, and envy others that can produce invariant geometry in their final products without resorting to post-assembly tweaking.

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A constellation only takes shape when one maps the whole.
- Beth Brower

Woodie said,
"they still appear to have to employ several different finished thicknesses on their bridges to address what appears to be an .080" - .100" difference between string height at the saddle"

I didn't know that and it is surprising. Since they hand set their dovetails I suspect neck angle is one of the factors.

The way I do it now is to glue the fingerboard to the neck, attach the neck to the body, camp the fingerboard down. No glue and I move the clamp around while leveling with a beam, take the neck off and install the frets, including the extension. That gives me the ability to finish off the fret ends before I do pore fill and finish. I like that part of it. I level, crown and polish the frets after the the guitar is assembled. (I am always glad that the frets ends are already done!)

I not sure what advantage I would gain if i finished and assembled first except for an occasional cutaway. (who plays on the extension of a non-cutaway anyway?)

Speaking of the extension, it seems to me that the subtle changes in geometry a guitar goes through in time because of RF changes would negate the advantages gained, but then I have been wrong before.

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Joe Beaver
Maker of Sawdust

To attain optimal results the components of the finest machinery in the world -- including production and racing engines are dimensionally matched. I don't think matching bridges to guitar body assemblies is odd or surprising -- its smart. Plus lets not forget our materials are organic -- do we not obsess over the effects of humidity?

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Ken Cierp

http://www.kennethmichaelguitars.com/

Goodness, that is the funniest thing I've read all day! Thanks for the dry wit and the belly laugh on a dreary, wet day, Mr. Cierpilowski.

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A constellation only takes shape when one maps the whole.
- Beth Brower

1.Ultimate.
2.Penultimate.
3.Antepenultimate.
4.Preantepenultimate.

AFAIK it doesn't go any further than that ..

[/quote]

1.Ultimate.
2.Penultimate.
3.Antepenultimate.
4.Preantepenultimate.

AFAIK it doesn't go any further than that ..[/quote]

UK guys know their English. Well done

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Joe Beaver
Maker of Sawdust